Use Calcium Chloride. sucrose doesn't break apart so it won't decrease the freezing point much, NaCl is better because you have twice as many ions running around than sucrose, and CaCl2 is the best because it has 3 ions dissolved instead of 1 or 2 like the others.
Convert the given density in mg/dL into a quantity with unit of g/L. This is shown below,
(200 mg / dL) x (10 dL / L) x (1 g / 1000 mg) = 2 g/L
Multiplying this quantity with the volume given, 5L, gives an answer of 10g.
Answer:
6.23 x 10^23 molecules
Explanation:
First find the number of moles of BH3 from the information given. We know the amount of grams present and we can find the molar mass which is 13.84.
We know that moles is grams divided by molar mass so we get 14.32/13.84 which is 1.03 moles.
Finally, to figure out the number of molecules, we multiply 1.03 by Avogadro's number which is 6.022x10^23 and we get 6.23x10^23 molecules.